#include<iostream>

using namespace std;

class Two {
    private:
        int y;
    public:
        friend class One;
        void show() {
            cout << "y = " << y << endl;
        }
};

class One {
    private:
        int x;
    public:
        One(int x,Two & two,int y) {
            this->x = x;
            two.y = y;
        }

        One() {}

};

int main() {
    Two two;
    One one(2,two,3);
    two.show();
    return 0;
}
